For #1, I’m not sure what you mean. If you have an image or additional description of what you mean maybe we can help.

You can modify the copyright text size with:

#socket {
font-size: 12px;
}

I’m not sure what you mean by the menu hiding parts of the page, on that example there isn’t any overlap that I can see.

For the product thumbnails, you can open and edit woocommerce-config>config.php and change the height of the shop_catalog array so that the height is the same as the width and force it to crop images. So change